摘要：The microstrip dual-mode filter （DMF） with conventional coupling structure has some limitations in- eluding the port coupling strength limited by fabrication tolerance and the existence of serious second order spuri- ous band. Therefore, a novel DMF with a offset-feed bended coupling structure and a stepped-impedance dual- mode resonator is proposed for coupling enhancement and spurious response suppression. Based on the analysis of the change of spur frequencies and the current distribution of spur resonant modes, all spurs near passband of the cascaded DMF can be fully suppressed by optimizing the structure parameters of parasite resonators, which bene- fits from the inherent well-controlled transmission zeros. Experimental results show that the proposed DMF ex- hibits lower insertion loss ,much sharper rate of cutoff and wider spur-free stop band compared with conventional DMF. This design is applicable for spur suppression in wideband communication.

摘要：To meet the requirements of the low power Zigbee system, VCO design optimizations of phase noise, power consumption and frequency tuning are discussed in this paper. Both flicker noise of tail bias transistors and up-conversion of flicker noise from cross-coupled pair are reduced by improved self-switched biasing technology, leading to low close-in phase noise. Low power is achieved by low supply voltage and triode region biasing. To linearly tune the frequency and get constant gain, distributed varactor structure is adopted. The proposed VCO is fabricated in SMIC 0.18-#m CMOS process. The measured linear tuning range is from 2.38 to 2.61 GHz. The oscillator exhibits low phase noise of-77.5 dBc/Hz and -122.8 dBc/Hz at l0 kHz and 1 MHz offset, respectively, at 2.55 GHz oscillation frequency while dissipating 2.7 mA from 1.2 V supply voltage, which well meet design specifications.

摘要：In recent years,using message ferries as mechanical carriers of data has been shown to be an effective way to collect information in sparse wireless sensor *** the sensors are far away from each other in such highly partitioned scenario,a message ferry needs to travel a long route to access all the sensors and carry the data collected from the sensors to the ***,practical constraints(e.g.,the energy)preclude a ferry from visiting all sensors in a single *** such case,the ferry can only access part of the sensors in each tour and move back to the sink to get the energy ***,the energy-constrained ferry route design(ECFRD)problem is discussed,which leads to the optimization problem of minimizing the total route length of the ferry,while keeping the route length of each tour below a given *** ECFRD problem is proved to be NP-hard problem,and the integer linear programming(ILP)formulation is *** that,efficient heuristic algorithms are proposed to solve this *** experimental results show that the performances of the proposed algorithms are effective in practice compared to the optimal solution.

摘要：本文针对目前主要的第三代压水堆机型EPR、AES2006以及CAP1400,从核电厂设计理念,综合性能、安全性和经济性等方面进行对比分析。在此基础上,结合福岛核事故,探讨中国商用核电未来的技术发展方向。通过对EPR、AES2006以及CAP1400的对比分析发现,尽管它们采用了不同的设计理念和技术方式,但作为目前第三代商用压水堆的代表机型,其目标都在于提高核电厂的整体性能、安全性能和经济性,从而在提高安全性的前提下,强化其相比于其他发电方式的竞争力,获得政府、公众和业主的支持。第三代压水堆技术的主要努力方向在于:在安全方面,进一步强化纵深防御体系,将设计加强工况(包括全厂断电、商用飞机撞击和预期未能停堆的瞬态等)纳入设计考虑的范畴;设置预防和缓解严重事故的措施;考虑极端外部事件设防(包括地震和洪水等)。再者,对非能动安全与能动安全两者之间的关系定位、相互衔接进行优化设置,从而更好的保障核安全。此外,严重事故下设备和仪表的可用性成为福岛核事故后需要特别关注的问题。从经济性的角度讲,加强设计简化和标准化,及时将EPR、AES2006以及CAP1400的首台组的建造经验反馈到后续机组,改进可建造性和模块化从而确保经济性和缩短建造周期。从运行的角度讲,考虑国内核电装机容量的增加、较长的设计寿命以及其他可再生能源的并网,核电设计需强化负荷跟踪的能力。长期来看,需要考虑可能的气候变化,从而确保核电站(沿海和内陆)具有较强的应对极端气候以及较高环境温度和冷却水升温的能力。

摘要：The radial force is a critical factor to determine the sealing performance of radial lip *** effects of radial force produced by garter spring and interference on the static contact properties and sealing performance of a radial lip seal are investigated by numerical simulations and ***-element analysis and mixed elastohydrodynamic lubrication simulation are *** force,contact width,temperature in the sealing zone,the reverse pumping rate and friction torque are measured.A critical value of interference for a cost-effectively designed radial lip seal is *** force is required to compensate the decrease of the radial force because of the interference and used as a possible way to obtain intelligent control of sealing *** quantitative results gotten in this study could provide guide for the seal design and improvement.

摘要：This paper addresses the gas path component and sensor fault diagnosis and isolation(FDI) for the auxiliary power unit(APU). A nonlinear dynamic model and a distributed state estimator are combined for the distributed control system. The distributed extended Kalman filter(DEKF)is served as a state estimator,which is utilized to estimate the gas path components’ flow capacity. The DEKF includes one main filter and five sub-filter groups related to five sensors of APU and each sub-filter yields local state flow capacity. The main filter collects and fuses the local state information,and then the state estimations are feedback to the sub-filters. The packet loss model is introduced in the DEKF algorithm in the APU distributed control architecture. FDI strategy with a performance index named weight sum of squared residuals(WSSR) is designed and used to identify the APU sensor fault by removing one sub-filter each time. The very sensor fault occurs as its performance index WSSR is different from the remaining sub-filter combinations. And the estimated value of the soft redundancy replaces the fault sensor measurement to isolate the fault measurement. It is worth noting that the proposed approach serves for not only the sensor failure but also the hybrid fault issue of APU gas path components and sensors. The simulation and comparison are systematically carried out by using the APU test data,and the superiority of the proposed methodology is verified.

摘要：The development of a high performance wideband radio frequency （RF） transceiver used in the next generation mobile communication system is presented. The developed RF transceiver operates in the 6 to 6.3 GHz band and the channel bandwidth is up to 100 MHz. It operates in the time division duplex （TDD） mode and supports the multiple-input multipleoutput （MIMO） technique for the international mobile telecommunications （IMT）-advanced systems. The classical superheterodyne scheme is employed to achieve optimal performance. Design issues of the essential components such as low noise amplifier, power amplifier and local oscillators are described in detail. Measurement results show that the maximum linear output power of the RF transceiver is above 23 dBm, and the gain and noise figure of the low noise amplifier is around 24 dB and below 1 dB, respectively. Furthermore, the error vector magnitude （EVM） measurement shows that the performance of the developed RF transceiver is well beyond the requirements of the long term evolution （LTE）-advanced system. With up to 8 x 8 MIMO configuration, the RF transceiver supports more than a 1 Gbit/s data rate in field tests.

摘要：This paper presents three compact ultra-wideband(UWB)antennas fed by coplanar waveguide(CPW).The proposed antennas consist of a planar circular patch monopole UWB antenna and multiple etched slots on the feed *** by Ansoft high frequency structure simulator(HFSS)10.0 shows that the in-band impedances are quite stable and *** narrow frequency bands are further obtained within the wideband width by inserting U-shaped slots into the fed line of the *** antennas have a dimension of 50mm by 40mm by *** simulation and measurement results show that the proposed antennas have stable directional radiation patterns,very low profile and low fabrication cost,which are suitable for the UWB system.

摘要：The current literature lacks uniform calculation methods for following trajectory control for autonomous vehicles,including the calculation of errors,determination of tracking points,and design of feedforward ***,a complete calculation method is proposed to address this ***,a control equation in the form of an error is obtained according to the dynamic equation of the vehicle coordinate system and the trajectory following ***,the deviation of the vehicle state is obtained according to the current vehicle s state and the following control ***,a linear quadratic regulator(LQR)controller with feedforward control is designed according to the characteristics of the dynamic *** the proposed LQR,the simulation of computational time,anti-interference,and reliability analysis of the trajectory following control is performed by programming using *** simulation outcomes are then compared with the experimental results from the *** comparison indicates that the proposed complete calculation method is effective,reliable,and capable of achieving real-time and anti-interference following control *** simulation results with or without feedforward control show that the steady-state error is eliminated and that good control performance is obtained by introducing feedforward control.

摘要：Rice(Oryza sativa)spikelets are a unique inflorescence structure and their development directly determines grain size and *** many genes related to spikelet development have been reported,the molecular mechanisms underlying this process have not been fully *** this study,we identified a new recessive rice mutant,lacking rudimentary glume 1(lrg1).The lrg1 spikelets only formed one rudimentary glume,which,along with the sterile lemmas,was homeotically transformed into lemma-like organs and acquired lemma *** transition from the spikelet to the floral meristem was delayed in the lrg1 mutant,resulting in the formation of an ectopic lemma-like organ between the sterile lemma and the terminal *** addition,we found that the abnormal lrg1 grain phenotype resulted from the alteration of cell numbers and the hull ***1 encodes a ZOS4-06-C2H2 zinc-finger protein with the typical EAR motifs,and is expressed in all organs and ***1 localizes to the nucleus and can interact with the TOPLESS-RELATED PROTEINs(TPRs)to repress the expressions of their downstream target *** together,our results reveal that LRG1 plays an important role in the regulation of spikelet organ identity and grain size.